Sound-modifier



H. LEGGETT.

SOUND MODIFIER. APPLICATION HLED APR. 13, 1920.

1,384,964, Patented July 19, 1921.

\I 4; 24 2 36 a ,2; :6 g 4 z a I J 12 '16 2 8 E 28 lo WITNESS: INVENTOR.

.Herber? lleyyeif,

[PM BY flfiafw,

ATTORNEY.

fiers, of which the spectively,

UNITED STATESR PAT ENTIO FFICE.

nmsnr Lneenrr, or KANSAS CITY, MISSOURI.

SOUND-MODIFIER.

To alt whom it may concern Be t known that I, HERBERT LEGGETT, a citizen of the United" States, residing at Iiansas City, in the county of Jackson and "State of Missouri, have invented certain new and useful Improvements in Sound-Modifollowing is a specification. Y

My invention relates to new and useful improvements in sound modifiers for inter- "nal combustion engines, and-my object is Fig. 3 is a central longitudinal section of i a modified form of the device.

Fig. 4 is a detail ofa modified form of sound modifier.

Fig. 5 is a detail of another modified form of sound modifier. In carrying out the invention, a tubular shell 2 closed at itsends by heads d 6 provided with flanges 8 and 10, rep which fit snugly within the ends of the shell 2. The head 4 is of conical form and has an axially disposed tubular duct 12 connected at its outer end to the exhaust pipe A of the gas engine (not shown) and provided with equally disposed peripheral )orts 14 through which the pulsating exhaust gases are equally distributed in the shell 2, to the end that the pressure in said shell may be more uniform than if said exhaust gases entered through a single side port. The inner end of the duct 12 is closed as indicated at 16 and has a threaded bore to receive the correspondingly threaded end of extending axially through the firmly against the shell 2.

Before threading the tie-rod 18 into the closed end 16 of the duct 12, said tie-rod is p Specification of Letters Patent. Application filed April 13,1920. 7 Serial modifying the pressure to affect the i an explosive engine Patented July 19, 1921. No. 373354.

equiped with one or ed by jamb nuts 30 and 32, respectively. The forward sound modifier 24 is positioned to abut the closed end '16 of the d the t1e-rod'18 is threaded into said closed By th n practice, it will be seen that this device can be readily applied to the exhaust pipe of and as the exhaust gases enter the shell 2 they first impinge a ainst the outer surface of the sound modi er 24 0mg, impinge against the conical wall of the second sound modifier 25 which directs the gases to the restricted annular passagey way 38 between the mouth of said modifier 25 and the shell 2. After passing through t e passageway 38 the exhaust gases escape to atmosphere through the outlet duct 20. e exhaust gases impinge against the outer surfaces of the sound modifiers 24 and sound waves occa- 25 which increase in volume as indicated by the irregular lines 6, and thus completely nullify the harsh tones aforementioned. I

The device disclosed by Fig. 3, is similar to the term disclosed by Fig. 1, as evidenced nents a, one sounding member 24* stead of two.

The sounding member 24*, Fig. 4, has 1ongitudinal slits 40 and the sounding member 24, Fig. 5, has perforations 42 and marginal notches 44 to give different tones from each other and the members 24 and 25.

ile I have shown yes sound modifiers of conical form I do not restrict myself to this particular shape for experience has shown that modifications of different forms, thicknesses and materials produce different results, and variety of tone may be had by providing the modifiers with slits, perforations, notches, etc. In all cases, the sounding member is suspended from-a point near the center and its outer edge is left free to vibrate.

It will thus be seen that I have made new and useful improvements in the articles de scribed and, what I claim as new and desire to secure by Letters Patent, is:

1. In a device of the character described, a shell, heads removably secured to the ends of said shell and provided respectively with inlet and outlet ports for the vpassage of exhaust gases, and a conical sound modifier arranged within the shell and supported at its reduced end only leaving its enlarged end free to vibrate from impactof the exhaust gases passing through the shell.

2. In a device of the character described, a shell, heads removably secured to the ends of said shell, an inlet duct to one of said heads having a closed inner end and equally-spaced peripheral ports for the passage of exhaust gases into the shell, an outlet duct in the companion head for the escape of a conical sound the exhaust gases, and

modifier arranged within the shell and supported at its reduced end only leaving its enlarged end free to vibrate from impact of the exhaust gases passing through the shell.

8. In a device of the character described,

a shell, heads removably secured to the ends of said shell and provided respectively with inlet and outlet ports for the passage of exhaust gases, a sound modifier within the shell and having a conical wall tapering in thickness toward its enlarged end, and a tierod extending axially through the shell to secure the heads and said sound modifier in place.

4. In a. device of the character described, a shell, heads rcmovably secured to the ends of said shell and provided respectively with inlet and outlet ports for the passage of exhaust gases, a tiered extending axially through the shell and said heads to secure them in assembled position, and a plurality of conical sound modifiers within the shell mounted at their reduced ends upon sai tierods and having their enlarged ends free to vibrate from impact of the exhaust gases passing through the shell.

5. In a device of the character described, a tubular shell, heads at the ends of said shell and provided respectively with inlet and outlet ports, bell-shaped sound modifiers axially disposed within the shell and supported at their reduced ends only which are directed toward the inlet port, substantially as shown and described.

In testimony whereof I affix mysignature in the presence of two witnesses.

HER-BERT LEGGETT.

Witnesses: p v

F. G. FISCHER, L. J. Frscmm. 

